B. Borrow: Satisfactory soil imported from off-site for use as fill or backfill.

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1 SECTION EARTHWORK PART 1 - GENERAL 1.1 RELATED DOCUMENTS Drawings and general provisions of the Contract, including General and Special Conditions, apply to this Section. 1.2 SUMMARY This Section includes the following: 1. Preparing subgrades for pavements. 2. Subbase course for asphalt paving. 3. Grading for lawn repair B. Related Sections include the following: 1. Division 32 Section "Lawns and Grasses" for finish grading, including placing and preparing topsoil for lawns and plantings. 1.3 DEFINITIONS Backfill: Soil materials used to fill an excavation. B. Borrow: Satisfactory soil imported from off-site for use as fill or backfill. C. Excavation: Removal of material encountered above sub grade elevations. 1. Additional Excavation: Excavation below subgrade elevations as directed by Engineer. Additional excavation and replacement material will be paid for according to Contract provisions for changes in the Work. 2. Bulk Excavation: Excavations more than 10 feet in width and pits more than 30 feet in either length or width. 3. Unauthorized Excavation: Excavation below subgrade elevations or beyond indicated dimensions without direction by Engineer. Unauthorized excavation, as well as remedial work directed by Engineer, shall be without additional compensation. D. E. F. G. Fill: Soil materials used to raise existing grades. Aggregate Base Course: Layer placed between the subgrade and black base course for asphalt paving. Sub grade: Surface or elevation remaining after completing excavation, or top surface of a fill or backfill immediately below subbase, drainage fill, or topsoil materials. Utilities include on-site underground pipes, conduits, ducts, and cables, as well as underground services within buildings. 1.4 SUBMITTALS Material Test Reports: From a qualified testing agency indicating and interpreting test results for compliance of the following with requirements indicated: SECTION EARTHWORK -1-

2 1. Laboratory compaction curve according to ASTM D 1557 for each on-site or borrow soil material proposed for fill and backfill. B. Material Data: Sieve analysis for specified aggregate. 1.5 QUALITY ASSURANCE Applicable Standards: 1. American Society for Testing and Materials as referenced. 2. Missouri Department of Transportation (MoDOT), Missouri Standard Specification for Highway Construction as referenced. B. Geotechnical Testing Agency Qualifications: An independent testing agency qualified according to ASTM E 329 to conduct soil materials and rock-definition testing, as documented according to ASTM D 3740 and ASTM E PROJECT CONDITIONS Existing Utilities: Do not interrupt utilities serving facilities occupied by Owner or others unless permitted in writing by Engineer and then only after arranging to provide temporary utility services according to requirements indicated: 1. Do not proceed with utility interruptions without Engineer's written permission. 2. Contact utility-locator service for area where Project is located before excavating. PART 2 -PRODUCTS 2.1 SOIL MATERIALS General: Provide borrow soil materials when sufficient satisfactory soil materials are not available from excavations. B. Satisfactory Soils: ASTM D 2487 soil classification groups GW, GP, GM, SW, SP, and SM, or a combination of these group symbols; free of rock or gravel larger than 3 inches in any dimension, debris, waste, frozen materials, vegetation, and other deleterious matter. C. Unsatisfactory Soils: ASTM D 2487 soil classification groups GC, SC, ML, MH, CL, CH, OL, OH, and PT, or a combination of these group symbols. 1. Unsatisfactory soils also include satisfactory soils not maintained within 2 percent of optimum moisture content at time of compaction. D. Backfill and Fill: Satisfactory soil materials. E. Aggregate Base: Naturally or artificially graded mixture of natural or crushed gravel, crushed stone, and natural or crushed sand; ASTM D 2940; with at least 90 percent passing a 1/2- inch sieve and not more than 35 percent passing a No. 30 sieve per MoDOT Specification Section , Type 1. F. 1/2-inch Clean Aggregate: Naturally or artificially graded mixture of natural or crushed gravel, crushed stone; ASTM D 2940; with 100 percent passing a 1- inch sieve and 95% retained on a 1/2-inch sieve. SECTION EARTHWORK -2-

3 PART 3 -EXECUTION 3.1 PREPARATION Protect structures, utilities, sidewalks, pavements, and other facilities from damage caused by settlement, lateral movement, undermining, washout, and other hazards created by earthwork operations. B. Protect subgrades and foundation soils against freezing temperatures or frost. Provide protective insulating materials as necessary. c. Provide erosion-control measures to prevent erosion or displacement of soils and discharge of soil-bearing; water runoff or airborne dust to adjacent properties and walkways. 3.2 DEWATERING B. Prevent surface water and ground water from entering excavations, from ponding on prepared sub grades, and from flooding Project site and surrounding area. Protect subgrades from softening, undermining, washout, and damage by ram or water accumulation. 1. Reroute surface water runoff away from excavated areas. Do not allow water to accumulate in excavations. Do not use excavated trenches as temporary drainage ditches. 2. Install a dewatering system to keep subgrades dry and convey ground water away from excavations. Maintain until dewatering is no longer required EXPLOSIVES Explosives: Do not use explosives. EXCAVATION, GENERAL Unclassified Excavation: Excavation to subgrade elevations regardless of the character of surface and subsurface conditions encountered, including rock, soil materials, and obstructions. 1. If excavated materials intended for fill and backfill include unsatisfactory soil materials and rock, replace with satisfactory soil materials. 3.5 EXCAVATION FOR WALKS AND PAVEMENTS Excavate surfaces under walks and pavements to indicated cross sections, elevations, and grades. 3.6 APPROVAL OF SUBGRADE Notify Engineer when excavations have reached required subgrade. B. If Engineer determines that unsatisfactory soil is present, continue excavation and replace with compacted backfill or fill material as directed. 1. Additional excavation and replacement material will be paid for according to Contract provisions for changes in the Work. SECTION EARTHWORK -3-

4 C. Proof roll sub grade with heavy pneumatic-tired equipment to identify soft pockets and areas of excess yielding. Do not proof roll wet or saturated sub grades. D. Reconstruct subgrades damaged by freezing temperatures, frost, rain, accumulated water, or construction activities, as directed by Engineer. 3.7 UNAUTHORIZED EXCAVATION Fill unauthorized excavation under pavements and trenches by extending bottom elevation of subbase to excavation bottom, without altering top elevation. Lean concrete fill may be used when approved by Engineer. 3.8 STORAGE OF SOIL MATERIALS Stockpile borrow materials and satisfactory excavated soil materials. Stockpile soil materials without intermixing. Place, grade, and shape stockpiles to drain surface water. Cover to prevent windblown dust. 1. Stockpile soil materials away from edge of excavations. Do not store within drip line of remaining trees. 3.9 BACKFILL Place and compact backfill in excavations promptly, but not before completing the following: 1. Surveying locations of underground utilities for record documents. 2. Inspecting and testing underground utilities. 3. Removing trash and debris. 4. Removing temporary shoring and bracing, and sheeting B. c. FILL Preparation: Remove vegetation, topsoil, debris, unsatisfactory soil materials, obstructions, and deleterious materials from ground surface before placing fills. Plow, scarify, bench, or break up sloped surfaces steeper than 1 vertical to 4 horizontal so fill material will bond with existing material. Place and compact fill material in layers to required elevations as follows: 1. Under grass and planted areas, use satisfactory soil material. 2. Under walks and pavements, use satisfactory soil material MOISTURE CONTROL Uniformly moisten or aerate subgrade and each subsequent fill or backfill layer before compaction to within 2 percent of optimum moisture content. 1. Do not place backfill or fill material on surfaces that are muddy, frozen, or contain frost or ice. 2. Remove and replace, or scarify and air-dry, otherwise satisfactory soil material that exceeds optimum moisture content by 2 percent and is too wet to compact to specified dry unit weight. SECTION EARTHWORK -4-

5 3.12 COMPACTION OF BACKFILLS AND FILLS Place backfill and fill materials in layers not more than 8 inches in loose depth for material compacted by heavy compaction equipment, and not more than 4 inches in loose depth for material compacted by hand-operated tampers. 1. Place backfill and fill materials evenly on all sides of structures to required elevations, and uniformly along the full length of each structure. B. Compact soil to not less than the following percentages of maximum dry unit weight according to ASTM D 698: 1. Under structures, building slabs, steps, and pavements, scarify and recompact top 12 inches of existing sub grade and each layer of backfill or fill material at 95 percent. 2. Under lawn or unpaved areas, scarify and recompact top 6 inches below subgrade and compact each layer of backfill or fill material at 85 percent GRADING General: Uniformly grade areas to a smooth surface, free from irregular surface changes. Comply with compaction requirements and grade to cross sections, lines, and elevations indicated. 1. Provide a smooth transition between adjacent existing grades and new grades. 2. Cut out soft spots, fill low spots, and trim high spots to comply with required surface tolerances. B. Site Grading: Slope grades to direct water away from buildings and to prevent ponding. Finish subgrades to required elevations within the following tolerances: 1. Lawn or Unpaved Areas: Plus or minus 1 inch. 2. Walks: Plus or minus 1 inch. 3. Pavements: Plus or minus 1/2 inch SUBBASE AND BASE COURSES Under pavements and walks, place subbase course on prepared sub grade and as follows: 1. Place base course material over subbase. 2. Compact subbase and base courses at optimum moisture content to required grades, lines, cross sections, and thickness to not less than 95 percent of maximum dry unit weight according to ASTM D Shape subbase and base to required crown elevations and cross-slope grades. 4. When thickness of compacted subbase or base course is 6 inches or less, place materials in a single layer. 5. When thickness of compacted subbase or base course exceeds 6 inches, place materials in equal layers, with no layer more than 6 inches thick or less than 3 inches thick when compacted FIELD QUALITY CONTROL Testing Agency: Owner may engage a qualified independent geotechnical engineering testing agency to perform field quality-control testing. SECTION EARTHWORK -5-

6 B. Allow testing agency to inspect and test subgrades and each fill or backfill layer. Proceed with subsequent earthwork only after test results for previously completed work comply with requirements. C. Testing agency will test compaction of soils in place according to ASTM D 1556, ASTM D 2167, ASTM D 2922, and ASTM D 2937, as applicable. Tests will be performed at the following locations and frequencies: 1. Paved Areas: At subgrade and at each compacted fill and backfill layer, at least one test for every 2000 sq. ft. or less of paved area, but in no case fewer than three tests. D B. When testing agency reports that subgrades, fills, or backfills have not achieved degree of compaction specified, scarify and moisten or aerate, or remove and replace soil to depth required; recompact and retest until specified compaction is obtained. PROTECTION Protecting Graded Areas: Protect newly graded areas from traffic, freezing, and erosion. Keep free of trash and debris. Repair and reestablish grades to specified tolerances where completed or partially completed surfaces become eroded, rutted, settled, or where they lose compaction due to subsequent construction operations or weather conditions. 1. Scarify or remove and replace soil material to depth as directed by Engineer; reshape and recompact. C. Where settling occurs before Project correction period elapses, remove finished surfacing, backfill with additional soil material, compact, and reconstruct surfacing. 1. Restore appearance, quality, and condition of finished surfacing to match adjacent work, and eliminate evidence of restoration to the greatest extent possible DISPOSAL OF SURPLUS AND WASTE MATERIALS Disposal: Remove surplus satisfactory soil and waste material, including unsatisfactory soil, trash, and debris, and legally dispose of it off Owner's property. END OF SECTION SECTION EARTHWORK -6-